1. Field of the Invention
This invention relates to en electric connection box (i.e., an electric junction block), such as a relay box, a fuse box and an ECU (electronic control unit) box, having an intensive electric circuit-connecting function provided within a box.
2. Related Art
Generally, an electric connection box is installed at an instrument panel within a passenger compartment of an automobile. However, a place where the electric connection box is installed at the instrument panel is usually considerably limited from the viewpoint of a vehicle design.
More specifically, the electric connection box does not belong to design parts, forming at least part of the interior decoration within the passenger compartment, and electric operating parts such as a switch, and therefore basically there is no vehicle design concept in which the electric connection box is allowed to be installed or mounted at those portions (e.g. a front portion or an upper portion) of the instrument panel which are important for the aesthetic appearance of the instrument panel and also for the operation of the electrical equipments.
Therefore, under the actual circumstances, the electric connection box must be mounted at an end portion (such as a lower end portion) of the instrument panel. On the other hand, in order to provide a comfortable compartment space, the on-board parts are always required to have a compact design so as to increase the compartment space.
Therefore, the electric connection box, incorporating branching/connecting circuits for wire harnesses for connection to electric parts (electrical equipments) provided at the instrument panel, function circuits, etc., is disposed at such a position (more specifically, at an end portion (such as a lower end portion) of the instrument panel as described above) that the wire harnesses must be laid out or installed long. Therefore, an improvement need to be made so that the electric connection box can be disposed at such a position that the wire harnesses can be laid out as short as possible. If the wire harnesses are thus laid out short, this can greatly contribute to the compact design, the reduction of the costs and the reduction of a DC resistance of a conductor of each wire harness.
Electrical connection between the wire harness and the electric connection box is made by fitting a plurality of connectors of the wire harness respectively to a plurality of connector portions provided at the electric connection box. Therefore, the number of connector-fitting operations is large, and therefore it is also necessary to improve the efficiency of the operation so as to reduce the cost (that is, a labor cost).
Incidentally, there is known an electric connection box-installation structure in which an electric connection box is provided at a rear surface of a meter mounted on a steering column (see JP-A-2005-184913 Publication). This installation structure is advantageous in that the electric connection box is positively disposed at the rear surface of the meter which is a main electric part of an automobile and that electrical connection between the electric connection box and the meter is made by connectors without using any wire harness.
However, in view of the above circumstances, it is more desirable that the electric connection box can be electrically connected to more electrical equipments.